1. Field of the Invention
The present invention relates to molding compounds which contain a thermoplastically processible, aromatic polyester imide.
2. Discussion of Background
Liquid crystalline polyester imides are known. However, among other things, due to their inherent color and low crystallinity they are unsatisfactory. Thus, in DE-OS No. 29 50 939 polyester imides containing 4-(4'-carboxyphthalimido)benzoic acid, 2,6-naphthalenedicarboxylic acid and a chloro- or alkyl-substituted hydroquinone or 4-(4'hydroxyphthalimido)phenol, 2,6-naphthalenedicarboxylic acid and a chloro- or alkyl-substituted terephthalic acid are described. Similarly, in U.S. Pat. No. 4,383,105, instead of naphthalenedicarboxylic acid, 6-hydroxy-2-naphthalenecarboxylic acid is added. However, these monomers are difficult to obtain, and thus, the polymers are uninteresting from an engineering point of view.
Polyester imides, which contain units of C.sub.8 - to C.sub.16 -alkylene-.alpha.,.omega.-bis(trimellitic acid imides) (DE-OS No. 35 16 427) or C.sub.2 - to C.sub.12 -alkylene-.alpha.,.omega.-bis(trimellitic acid imides) (EP-OS No. 0 213 362), do not exhibit the desired high thermal stability.
From DE-OS No. 35 42 857 and EP-OS No. 0 225 537 polyester imides are known that are derived from bis(trimellitic acid imides) of mononuclear or binuclear diamines.
Thus, there remains a need for aromatic polyester imides that are liquid crystalline, preferably in the melt, and that exhibit a combination of good melt flow properties, excellent impact and notch resistance, high rigidity, and high thermal stability. There is also a need for molding compounds based on such thermoplastically processible aromatic polyester imides.